Treatment and Healthcare Cost Among Patients with Hip or Knee Osteoarthritis: A Cross-sectional Study Using a Real-world Claims Database in Japan Between 2013 and 2019.

Abstract

The guidelines for osteoarthritis (OA) treatment recommend different therapies including pharmacotherapy, and several analgesic options are available for pain management. In Japan, research on hip and knee OA treatment trends is scarce and OA-related healthcare costs are unknown. Therefore, this study aimed to examine the treatment and healthcare cost trends among Japanese patients with hip or knee OA. This was a cross-sectional study held between 2013 and 2019, using a medical claims database. The demographic and treatment characteristics of hip or knee OA patients for each year were descriptively analyzed and the medians for healthcare utilization and all-cause healthcare costs were calculated. The yearly mean age of 59,218 hip OA and 270,722 knee OA patients ranged from 66.3 to 68.6years and 71.1 to 73.1years, respectively. The prevalence of comorbidities was higher in knee OA than hip OA. In both groups, > 70% of patients were female, and the most common treatment was pain-related medication. In hip OA, topical and systemic nonsteroidal anti-inflammatory drugs (NSAIDs) were mostly used throughout the study period (34.1-41.4% and 32.0-40.3%, respectively). Similarly, in knee OA, topical and systemic NSAIDs were used in 58.3-63.3% and 36.5-46.0% patients, respectively. Increase in the use of acetaminophens (10.9% in hip OA and 10.2% in the knee OA) and weak opioids (3.7%, and 3.4%, respectively) from 2013 to 2019 were observed. Most patients were treated as outpatients in both groups. The median all-cause healthcare costs were approximately 35,000 JPY for hip OA and 74,000 JPY for knee OA. Although a considerable change in total healthcare cost was not observed in our study, the contents of medical treatment and cost breakdown were greatly altered due to the treatment and cost for OA itself, and the treatment and cost for comorbidities. Similar studies to investigate such a trend may help predict necessary resources and social needs. Thus, further investigation utilizing other databases is needed.